Luggage tag technique of anatomic fixation of displaced acromioclavicular joint separations

Anatomic reconstruction of acromioclavicular joint dislocations using allograft and synthetic ligament

Background

Acromioclavicular (AC) separations are commonly seen shoulder injuries. Numerous surgical reconstruction techniques have been described. In this study, we present a series of patients who underwent an anatomic reconstruction using a synthetic ligament and allograft construct.

Methods

We performed a retrospective review of patients with type IV or V AC separations who underwent primary or revision AC reconstruction with a luggage-tag synthetic ligament and a semitendinosus allograft placed through the anatomic insertion sites of the coracoclavicular ligaments. Patient-reported outcomes, as well as complication rates, were recorded at a minimum 2-year follow-up.

Results

Ten patients with a mean age of 44.2 ± 14.9 years were included in the study. The mean Disabilities of the Arm, Shoulder and Hand score was 15.5 ± 15.4; mean Single Assessment Numeric Evaluation score, 81.8 ± 12.1; mean Simple Shoulder Test score, 11.4 ± 1.1; mean American Shoulder and Elbow Surgeons score, 84.6 ± 15.7; mean Constant score, 82.5 ± 11.6; and mean visual analog scale score, 2 ± 2.6.

Conclusion

The technique using a luggage-tag synthetic ligament along with an anatomic allograft coracoclavicular ligament reconstruction is a safe, effective alternative to other techniques described in the literature.

Single coracoclavicular suture fixation with Mersilene tape versus hook plate in the treatment of acute type V acromioclavicular dislocation: a retrospective analysis

BACKGROUND

Here, we compared the clinical and radiographic outcomes between coracoclavicular (CC) fixation with Mersilene tape and hook plate for acute unstable acromioclavicular (AC) joint dislocation treatment.

METHODS

We enrolled 49 patients with unstable acute AC dislocation who, between January 2010 and January 2014, underwent surgery with single CC suture fixation with Mersilene tape (M group, 25 cases) or clavicle hook plate (H group, 24 cases). In M and H groups, the average age was 43.7 (range 18-72) and 42.0 (range 17-84) years, the male to female ratio of each group was 15:20 and 19:5, and the injured side left to right ratio was 12:13 and 11:13, respectively. All patients were right-handed. We retrospectively compared the operation time, complication rate, visual analog scale (VAS), University of California at Los Angeles (UCLA) shoulder rating scale, Oxford shoulder scores, and the radiographic outcomes based on reduction loss of CC distance on postoperative follow-up.

RESULTS

No significant difference in patient demographics between the two groups in age (p = 0.709), gender (p = 0.217), time from injury to surgery (p = 0.863), and injured side (p = 1.000). The mean follow-up was 26.2 months (range 24-35 months). Nine cases of reduction loss (36%) and one of distal clavicle osteolysis (4%) were noted in the M group. CC distance improvement in the H group was significantly superior to that in the M group at 3 months (before hook plate removal, p < 0.001) and 12 months postoperatively (after hook plate removal, p = 0.004), while subacromial erosions were revealed in nine cases (37.5%) in the H group. No significant difference in operative time (p = 0.846), complication rate (p = 1.000), VAS (p = 0.199), mean UCLA shoulder rating scale (p = 0.353), and Oxford shoulder (p = 0.224) scores between the two groups.

CONCLUSIONS

Both hook plate and Mersilene tape fixations provided temporary stabilization of acute type V AC dislocation and yielded comparable clinical outcomes. The hook plate provided better maintenance of reduction of radiographic outcomes. CC suture fixation with Mersilene tape may serve as an alternative method of stabilization which provides acceptable outcome without the need of implant removal.

Biomechanical evaluation of native acromioclavicular joint ligaments and two reconstruction techniques in the presence of the sternoclavicular joint: A cadaver study

BACKGROUND

Where is over 100 reconstruction techniques described for acromioclavicular (AC) joint reconstruction. Although, it is not clear whether the presence of the sternoclavicular (SC) joint influences the biomechanical properties of native AC ligaments and reconstruction techniques. The purpose of the present study was to investigate the biomechanical properties of native AC joint ligaments and two reconstruction techniques in cadavers with the SC joint still present.

MATERIALS AND METHODS

We tested eight fresh-frozen cadaver hemithoraces for superior translation (70 N load) and translation increment after 1000 cycles (loading from 20 to 70 N) in a controlled laboratory study. There were three testing groups created: native ligaments, the single coracoclavicular loop (SCL) technique, and the two coracoclavicular loops (TCL) technique. Superior translation was measured after static loading. Translation increment was calculated as the difference between superior translation after cyclic and static loading.

RESULTS

Native AC ligaments showed significantly lower translation than the SCL ( p = 0.023) and TCL ( p = 0.046) groups. The SCL had a significantly lower translation increment than native AC ligaments ( p = 0.028). There was no significant difference between reconstruction techniques in terms of translation ( p = 0.865) and translation increment ( p = 0.113).

CONCLUSIONS

Native AC joint ligaments had better static properties than both reconstruction techniques and worse dynamic biomechanical properties than the SCL technique. The SCL technique appeared to be more secure than the TCL technique. The presence of the SC joint did not have an observable influence on test results.

Anatomical Evaluation of the Proximity of Neurovascular Structures During Arthroscopically Assisted Acromioclavicular Joint Reconstruction: A Cadaveric Pilot Study

PURPOSE

The purpose of this study was to examine the safety of an arthroscopic technique for acromioclavicular joint (ACJ) reconstruction by investigating its proximity to important neurovascular structures.

METHODS

Six shoulders from 4 cadaveric specimens were used for ACJ reconstruction in this study. The procedure consists of performing an arthroscopic acromioclavicular (AC) reduction with a double button construct, followed by coracoclavicular ligament reconstruction without drilling clavicular tunnels. Shoulders were subsequently dissected in order to identify and measure distances to adjacent neurovascular structures.

RESULTS

The suprascapular artery and nerve were the closest neurovascular structures to implanted materials. The mean distances were 8.2 (standard deviation [SD] = 3.6) mm to the suprascapular nerve and 5.6 (SD = 4.2) mm to the suprascapular artery. The mean distance of the suprascapular nerve from implants was found to be greater than 5 mm (P = .040), while the distance to the suprascapular artery was not (P > .5). Neither difference was statistically significant (P = .80 for artery; P = .08 for nerve).

CONCLUSIONS

Mini-open, arthroscopically assisted ACJ reconstruction safely avoids the surrounding nerves, with no observed damage to any neurovascular structures including the suprascapular nerve and artery, and may be a viable alternative to open techniques. However, surgeons must remain cognizant of possible close proximity to the suprascapular artery.

CLINICAL RELEVANCE

This study represents an evaluation of the safety and feasibility of a minimally invasive ACJ reconstruction as it relates to the proximity of neurovascular structures.

BIOMECHANICAL COMPARISON OF THE CORACOCLAVICULAR SPACE FIXATION USING THREE DIFFERENT SUTURE TECHNIQUES

Coracoclavicular space fixation with suture loops is a well-known surgical technique for the treatment of dislocations. However, out of 100 different surgical treatments no single one has been established as a gold standard. The following research aims to improve the technique and focuses on a development of new fixation technique using composite sutures, which would withstand forces during ligament healing process. Three different fixation techniques (one loop and two separate suture loops and W-system) were tested on a custom built mechanical testing device. Applied load was continuously increased at a loading rate of 30[Formula: see text]N/min until the failure of the sutures. Ultimate tensile strength and suture elongation at failure were measured. The W-system had statistically significant higher load to failure and higher stiffness compared to one loop and two separate loops techniques. Biomechanical properties of a suture fixation technique can be improved by connecting them into one system to create particular arrangement of the sutures. The measurements can be easily repeated and this testing protocol can serve as a good starting point to standardize procedures of evaluation of different joint fixation techniques and to develop new ones.

Coracoclavicular ligament reconstruction: a systematic review and a biomechanical study of a triple endobutton technique

Operative intervention is recommended for complete acromioclavicular (AC) joint dislocation to restore AC stability, but the best operative technique is still controversial. Twelve fresh-frozen male cadaveric shoulders (average age, 62.8±7.8 years) were equally divided into endobutton versus the modified Weaver-Dunn groups. Each potted scapula and clavicle was fixed in a custom made jig to allow translation and load to failure testing using a Zwick BZ2.5/TS1S material testing machine (Zwick/Roell Co, Germany). A systematic review of 21 studies evaluating reconstructive methods for coracoclavicular or AC joints using a cadaveric model was also performed. From our biomechanical study, after ligament reconstruction, the triple endobutton technique demonstrated superior, anterior, and posterior displacements similar to that of the intact state (P>0.05). In the modified Weaver-Dunn reconstruction group, however, there was significantly greater anterior (P<0.001) and posterior (P=0.003) translation after ligament reconstruction. In addition, there was no significant difference after reconstruction between failure load of the triple endobutton group and that of the intact state (686.88 vs 684.9 N, P>0.05), whereas the failure load after the modified Weaver-Dunn reconstruction was decreased compared with the intact state (171.64 vs 640.86 N, P<0.001). From our systematic review of 21 studies, which involved comparison of the modified Weaver-Dunn technique with other methods, the majority showed that the modified Weaver-Dunn procedure had significantly (P<.05) greater laxity than other methods including the endobutton technique. The triple endobutton reconstruction proved superior to the modified Weaver-Dunn technique in restoration of AC joint stability and strength. Triple endobutton reconstruction of the coracoclavicular ligament is superior to the modified Weaver-Dunn reconstruction in controlling both superior and anteroposterior displacements with a failure load that approximates the intact ligament.

Acromioclavicular joint dislocations: radiological correlation between Rockwood classification system and injury patterns in human cadaver species

INTRODUCTION

The classification system of Rockwood and Young is a commonly used classification for acromioclavicular joint separations subdividing types I-VI. This classification hypothesizes specific lesions to anatomical structures (acromioclavicular and coracoclavicular ligaments, capsule, attached muscles) leading to the injury. In recent literature, our understanding for anatomical correlates leading to the radiological-based Rockwood classification is questioned. The goal of this experimental-based investigation was to approve the correlation between the anatomical injury pattern and the Rockwood classification.

MATERIALS AND METHODS

In four human cadavers (seven shoulders), the acromioclavicular and coracoclavicular ligaments were transected stepwise. Radiological correlates were recorded (Zanca view) with 15-kg longitudinal tension applied at the wrist. The resulting acromio- and coracoclavicular distances were measured.

RESULTS

Radiographs after acromioclavicular ligament transection showed joint space enlargement (8.6 ± 0.3 vs. 3.1 ± 0.5 mm, p < 0.05) and no significant change in coracoclavicular distance (10.4 ± 0.9 vs. 10.0 ± 0.8 mm). According to the Rockwood classification only type I and II lesions occurred. After additional coracoclavicular ligament cut, the acromioclavicular joint space width increased to 16.7 ± 2.7 vs. 8.6 ± 0.3 mm, p < 0.05. The mean coracoclavicular distance increased to 20.6 ± 2.1 mm resulting in type III-V lesions concerning the Rockwood classification.

CONCLUSIONS

Trauma with intact coracoclavicular ligaments did not result in acromioclavicular joint lesions higher than Rockwood type I and II. The clinical consequence for reconstruction of low-grade injuries might be a solely surgical approach for the acromioclavicular ligaments or conservative treatment. High-grade injuries were always based on additional structural damage to the coracoclavicular ligaments. Rockwood type V lesions occurred while muscle attachments were intact.

Hook plate fixation for acromioclavicular joint separations restores coracoclavicular distance more accurately than PDS augmentation, however presents with a high rate of acromial osteolysis

INTRODUCTION

Hook plate fixation of acromioclavicular (AC) joint separations carries the disadvantage of compulsory implant removal, occasional implant fatigue and secondary loss of reduction. This study compares the clinical and radiological outcome of a new polyaxial angular stable hook plate (HP) with absorbable polydioxansulfate (PDS) sling.

MATERIALS AND METHODS

Between 2002 and 2009, out of a consecutive series of 81 patients with symptomatic Rockwood type V lesions 52 patients received clinical and radiographic follow-up (HP: n = 27; PDS: n = 25). HP patients were prospectively analyzed and retrospectively compared with the PDS group. Radiological follow-up included comparative coraco- and acromioclavicular distance (CCD/ACD) measurements as percentage of the uninjured shoulder. For clinical follow-up a standardized functional shoulder assessment with Constant Score, DASH Score, Taft Score and a self-report questionnaire including the visual analog scale (VAS) was carried out.

RESULTS

Direct postoperative radiographs showed an overcorrection of CCD in the HP group (-4.4% of the uninjured side) and failure of anatomic correction in the PDS group (+11.0%). After implant removal, CCD increased in the HP group extensively to 16.7% (overall loss of reduction: 21.1%) and 23.9% in the PDS group. Redisplacement (100% increase of CCD) occurred in five cases (HP: 2, PDS: 3) and partial loss of reduction in four cases of each group. Comparing functional results no differences could be seen between both the groups (Constant-Score HP: 91.2 points, PDS: 94.6 points; Taft-Score HP: 9.4 points, PDS: 10.0 points). The DASH-Score revealed better results for PDS group (3.4 points, HP: 8.0 points). Signs of acromial osteolysis appeared in five cases (18.5%) in HP group. There was no case of implant failure. The X-rays of six patients (HP: 4, PDS: 2) showed AC-joint-osteoarthritis.

CONCLUSION

Hook plate fixation employing a polyaxial angular stable plate finally restores the coracoclavicular distance more accurately than augmentation with a PDS sling. Although in HP group no implant failure occurred, major disadvantages are initial overcorrection and acromial osteolysis. Both have no influence on final functional results.